adj · noun · 4 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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General-American:/ˌsɛˌmaɪsnˈtɛniəl/
General-American:/ˌsɛmisnˈtɛniəl/
General-American:/ˌsɛˌmaɪsənˈtɛniəl/
General-American:/ˌsɛmisənˈtɛniəl/
Received-Pronunciation:/ˌsɛmɪsɛnˈtɛnɪəl/
1
adj
Meaning 1
Of or related to a 50th anniversary, occurring every 50 years.
Definition source: English Wiktionary via Wiktextract
Usage: not-comparable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
A 50th anniversary.
Definition source: English Wiktionary via Wiktextract
Examples
The city celebrated its semicentennial last year.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
adjective
Meaning 3
of or relating to or marking the 50th anniversary
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: semicentenary
Antonyms: none provided
4
noun
Meaning 4
the 50th anniversary (or the celebration of it)
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: semicentenary
Antonyms: none provided
Broader terms: anniversary, day of remembrance
History
Etymology
From semi- (“half”) + centennial (“100 year, 100th anniversary”), q.v.
Across languages
Translations
1 source translations are retained for this English entry.